Bit for diamond drills



Patented Nov. I, I898.

G. VDLLATH.

BIT FOR DIAMOND DRILLS.

(Application filed June 1, 1896 (No Model.)

Attorney w%/////////////// millhlLll 2%- 2 1 NiTE rArEs' ATENT eEoRcEVOLLATH, or FARMINGTON, MISSOURI, ASSIGNOR TO HIMsELE AND DEDERIGKBAUMAN, OF SAME PLACE, AND OLIVER H. PICHER,

OF .IOPLIN, MISSOURI.

BIT FOR DIAMOND DRILLSI SPECIFICATION forming part of Letters Patent No.613,340, dated iil'ovembi- 1, 1898.

Application filed June 1, 1896. Serial No. 593,689. (N0 model.)

To aZZ whom it may concern.-

Be it known that I, GEORGE VOLLATH, a citizen of the United States,residing at Farmington, in the county of St. Francois, in the State ofMissouri, have invented a certain new and useful Improvement in Bits forDiamond Drills, of which the following is a true and exact description,reference being had to the accompanying drawings, which form a partthereof.

My invention relates to the bits used in connection with what are knownas diamond drills, and particularly to what are known as solid bits,with which it is customary to work until a mineral-bearing zone isreached, when the core-bit is substituted for the solid bit.

Quite generally the solid bit used is made up of the core-bit and aninner solid bit fitting in-the cylindrical center of the core-bit andfirmly clamped in position, so that the annular and solid bits work asand practically are one solid bit, while the inner solid bit can beeasily removed when desired.

As solid bits have heretofore been constructed they have been providedwith a central hole or perforation through which water is passed to thecutting-face of the drill and through which a small core forces itselfupward. The advantage of preserving this core is, however, very small,because it is always very imperfect and because in working through theground until a mineral-bearing zone is reached the character of theground can be ascertained quite satisfactorily by means of the sludgeforced up on the outside of the bit and drilling-tubes; but while forthe reasons given these small cores are of but little value they provein practice a source of great trouble, owing to their tendency to breakup and jam in the central perforation of the solid bit, in which casethey not only prevent the bit from passing downward properly, but alsocut off the supply of water necessary to cool the bit and carry thesludge upward. Now my object is to improve the solid bit so as toobviate the danger of jamming, and I accomplish this, primarily,byproviding a bit with two or more longitudinal perforations, but one ofwhich of course can be a central perforation, also by making the centralperforation, which I prefer to use, although it is not essential, ofquite small di ameter, so as to insure the cutting and breaking up ofthe rock which passes through it; also, I form my bit with a transversegroove extending from side to side on the face of the bit andcommunicating with the ends of the longitudinal perforations, thisgroove being for the purpose of permitting the free passage of sludge tothe outside of the bit. Preferably I form the solid bit in the usualway, using the core-bit and the inner solid bit to make up the compositesolid bit, and in this case I form slots through the face of thecorebits edge,which register with and form a continuation of thetransverse groove in the face of the inner solid bit.

Reference is now had to the drawings, in which my improved bit isillustrated in its preferred construction, and in which- Figure 1 is alongitudinal section on the line 1 1 of Fig. 2; Fig. 2, a longitudinalsection on the line 2 2 of Fig. 1; Fig. 3, an end view; Fig. 4c,a sideelevation of the internal solid bit, and Fig. 5 a side elevation of thecore-bit.

A indicates the core-shell, having an inner shoulder A and aninternally-threaded extension A B is a core-bit having an externalshoulder 13 and an externally-threaded extension B which screws into theinternally-threaded extension A of the core-shell.

O is the solid bit, which, as shown, is provided with an annularshoulder O, which in practice is clamped between the shoulder A and thetop of the threaded extension B and with laterally-extending lugs C C,which fit into slots B in the top of the extension 13 of the core-bit,and thus lock the inner and outer bit portions together.

0 indicates a transverse groove on the face of the inner solid bit,which preferably is made to register with and open into slots B B formedin the edge of the core-bit.

C is a central perforation in the solid bit, which preferably is made ofconsiderably less diameter than has heretofore been the case and of suchdiameter that the projecting edges of the diamonds set upon its edgewill out and break up the rock through which the drill is passing,preventing the formation of a core which would pass through theperforation C The necessary and proper area for the passage of water tothe face of the bit B is provided for by eccentric perforations, asindicated at 0 C and preferably all of the perforations should open intothe sludgegroove C so that thewater Will have an uninterrupted passagefrom the tubular coreshell through the bit and to the outside of thebit.

My construction by which I provide two, and preferably1nore,perforations for the passage of water to the face of the bit isadvantageous not only in permitting me to decrease the size of thecentral perforation, so as to avoid the formation of a core, but alsobecause in case of the jamming of material in any one perforation thereis still suflicient area for the passage of Water left in the otherperforations, and such jams as from time to time occur are therefore notmischievous, and owing to the free passage of water and sludge throughthe unjammed perforations and the sludge-slot the jams as a rule are ofbut short duration and do not require the lifting of the drill for theirremoval.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. A solid bit for diamond drilling having a small central perforation,one or more additionalperforations and a transverse sludgegroove as O onits face connecting the ends of said perforations.

2. The combination with a core-bit as B- of an inner bit as 0 having twoor more lon- 40 gitudinal perforations for the passage of water and atransverse sludge-groove as C on its face with which said perforationscommunicate.

3. The combination with a core-bit as B having transverse sludge-slots BB of an inner solid bit as O haxing a sludge-groove C arranged toregister with slots B a small central perforation and one or moreeccentric perforations all communicating with the 50 sludge-groove.

GEORGE VOLLATLL WVitnesses:

MERRILL PIPKIN, W. H. YOUNG;

